The invention relates to a device for dividing laminated glass with the features of the introductory part of claim 1.
Devices for dividing laminated glass are known for example from U.S. Pat. No. 4,471,895 or U.S. Pat. No. 5,704,959.
In the known devices for dividing laminated glass, the latter is scratched on both sides along the intended dividing line and then bent first to the one and then to the other side (arched) or buckled in order to open the break along the scratch lines. This bending or buckling takes place in the known devices by pressure strips or pressure rollers or by one of the support surfaces on which the laminated glass to be divided rests being swivelled relative to the other support surface around an axis which is aligned parallel to the scratch line (U.S. Pat. No. 5,704,959).
Since the support surfaces must be so large that the laminated glass is supported over its entire surface, the means for swivelling one part of the support surfaces represent a major mechanical effort.
The object of the invention is to devise a device of the initially mentioned type with which the laminated glass which has been scratched on both sides can be broken with less effort.
This object is achieved as claimed in the invention by the features named in claim 1.
Preferred and advantageous embodiments of the device as claimed in the invention are the subject matter of the dependent claims.
In the device as claimed in the invention it is no longer necessary to swivel one of the two support surfaces relative to the other support surface in order to open the break in the glass panes of the laminated glass (by buckling it), but the two beams are simply swivelled such that on the one hand the laminated glass is convexly arched in one and then the other direction so that the fracture which lies on the side of the laminated glass which is convex at the time opens along the scratch line which was produced beforehand. In doing so the support surfaces and the areas of the laminated glass which lie on them remain stationary, i.e. the beams move independently of the support surfaces.
In one preferred embodiment of the device as claimed in the invention the beams are made as suction beams so that the laminated glass is held securely on the beams by negative pressure. Thus the clamping beams which are necessary in the known devices and which are pressed with great force from overhead against the laminated glass are unnecessary.
In principle, it is sufficient for the device as claimed in the invention if it is equipped with two swivelling beams when the already scratched laminated glass is conveyed onto the device. But it is also possible to equip the device as claimed in the invention with means for scratching the two panes of the laminated glass.
In the same way the device as claimed in the invention can have a means with which plastic film which is held between the two panes of laminated glass can be severed after breaking along the dividing line. These devices can be made as in the prior art. It is especially preferred within the framework of the invention if the plastic film is melted by the action of heat (heat radiation) after the fracture has been opened. The film can be cut within the framework of the invention also using a blade which travels along the fracture which has then been opened and cuts through the film.
It is especially preferred that heat radiation be used with a wavelength which is absorbed to an intensified degree only by the plastic film, but not by the two glass panes so that only the plastic film, but not the two glass panes, heats up when the plastic film is melted.